9 Best Supplements for Cats With Kidney Disease in 2026 - Reviews & Top Picks

Your cat was just diagnosed with kidney disease, and you want to do everything you can to help support their kidney function. Your veterinarian suggests a diet designed to support the kidneys, but are there any supplements you can give your cat to help promote kidney health? Let's look at some of the best supplements you can give your cat to support their urinary tract.

A Quick Comparison of Our Favorites in 2026

Rating	Image	Product	Details
Best Overall		Purina Hydra Care	Increases your cat's daily fluid intake Easy to administer	Check Price
Best Value		Purina Urinary Health Crunchy Cat Treat	Gives cats on prescription urinary food a treatment option Easy to administer Contains antioxidants	Check Price
Premium Choice		Dechra Porus One Kidney Powder	Helps remove harmful uremic toxins Simple once-daily use Generally well tolerated by cats	Check Price
		VetriScience Renal Essentials	Includes adaptogens like Cordyceps sinensis and omega-3 fatty acids Comes in chicken and fish flavors Affordable price	Check Price
		Nutramax Welactin Omega-3 Fish Oil Liquid Skin & Coat Supplement	Quality of the fish oils in Welactin is less likely to give your cat a fishy smell Potentially useful for a range of health issues	Check Price

The 9 Best Supplements for Cats With Kidney Disease

1. Purina Hydra Care – Best Overall Kidney Supplement

Getting enough fluids is essential for cats with kidney disease. To improve your cat's hydration, Purina created Purina Pro Plan Veterinary Supplements Hydra Care. The product comes in pouches, and your cat needs to consume at least 2 ounces per 5 pounds of body weight daily. The components called osmolytes help cats absorb fluid on a cellular level.

When administering this supplement, monitor your cat as a few people reported their cat experienced mild stomach upset, leading to vomiting and diarrhea.

2. Purina Urinary Health Crunchy Cat Treat – Best Value

Purnia snags another spot on the list! Giving our pets a snack is a bonding experience for many of us. You should be careful not to provide too many calories, but the Purina Urinary Health Crunchy Cat Treat is designed to promote urinary health in our kitties. It is actually used with cats that may be at risk for developing bladder or kidney stones (struvite or calcium oxalate), but it also contains antioxidants.

3. Dechra Porus One Kidney Powder Review – Premium Choice

The Dechra Porus One Kidney Powder is our premium choice for the best supplements for cats with kidney disease. This option is a renal support supplement designed for cats with chronic kidney disease (CKD). The formula uses a carbon-based adsorbent called Renaltec, which helps bind and remove harmful uremic toxins in the digestive tract before they reach the kidneys. This may help reduce kidney workload and support long-term renal health when used alongside a veterinarian-approved treatment plan.

One of the biggest benefits of Porus One is its simple administration. The tasteless powder comes in pre-measured sachets that can be mixed directly into wet food without significantly changing flavor or texture, making it easier for picky cats to tolerate. Many owners also appreciate that it can be combined with prescription kidney diets and other supplements rather than replacing them entirely.

While Porus One may help support cats with kidney disease, it is not a cure and works best as part of ongoing veterinary care.

4. VetriScience Renal Essentials

Another top choice on our list is VetriScience Renal Essentials. If you are looking for a chewable supplement that maintains kidney function by supporting homocysteine balance, normal fluid retention, stress management, homocysteine balance, and liver functions, this is your answer. This supplement encompasses everything you'd need in a kidney health supplement, such as B vitamins and fish oils, at an affordable price. In addition, its ingredients help establish healthy kidney blood flow.

One issue some people had was with the size of the tablet. Some felt it was too large for their cat, so they had to dissolve the tablets in water and administer them with a syringe.

5. Nutramax Welactin Omega-3 Fish Oil Liquid Skin & Coat Supplement for Cats

Fish oils have a wide range of benefits that you might already be familiar with, such as improving your cat's coat and skin. Did you know they can also lower blood pressure and decrease protein loss through the kidneys? Welactin is a quality fish oil supplement containing two major omega-3 fatty acids, EPA and DHA.

Since it is in liquid form, some cats might not like the taste.

6. Vetoquinol Azodyl Kidney Health Supplement

Vetoquinol Azodyl Kidney Health Supplement contains beneficial bacteria that help eliminate wastes that build up because the kidneys aren't working effectively. The supplement tends to be well-tolerated in both dogs and cats. Another positive for this formula is that it contains three beneficial bacterium: S. thermophilus, L. acidophilus, and B. longum.

7. Epakitin Chitosan-Based Phosphate Binder

When cats have kidney disease, their phosphorus levels can increase. High phosphorus levels are associated with decreased longevity, so getting those levels under control is essential. Using a phosphate binder like Epakitin helps bind phosphorus as your cat eats it and keeps it in the gastrointestinal tract, where it can be excreted.

Supplements of any kind can be a bit tricky, so some cats might not like the taste of the powder.

8. Zesty Paws Cranberry Bladder Bites

Urinary tract infections are more common in cats with renal disease than cats with a healthy pair of kidneys because the urine is more dilute in cats with kidney disease. Cranberry supplements like Zesty Paws Cranberry Bladder Bites may have some bladder-protective properties. This formula contains D-mannose, which helps maintain healthy urinary tract function. Additionally, the Zesty Paws chews contain vitamin B6 (80 mcg per two chews), helping with immune system support.

9. Pfizer Animal Pet-Tinic Vitamin-Mineral Supplement

Some cats with renal disease have a decreased appetite, so they may not get all the nutrients they need from their food. Pet-Tinic supplements iron and several vitamins, which can be necessary for red blood cell production and immune support.

Buyer’s Guide: Understanding Kidney Disease in Cats

Unfortunately, kidney failure is very common in cats. According to VCA Animal Hospitals, 81% of cats over 15 have kidney disease. A variety of factors can cause kidney disease:

• Genetics
• Neoplasia
• Infections
• Kidney stones (nephroliths)

Your veterinarian will diagnose kidney disease based on several tests. They'll typically start with blood work and a urinalysis. Possible changes in laboratory values associated with kidney disease include:

• Elevated BUN (blood urea nitrogen) and Creatinine
• Elevated SDMA
• Decreased urine specific gravity
• Increased protein in the urine
• Decreased red blood cell count
• Increased blood pressure

Dietary management is the mainstay of treating kidney disease. Several prescription diets aim to support the kidneys by restricting protein and phosphorus intake. Research into supplements is ongoing, with variable results. Make sure you discuss any supplements with a veterinarian to ensure they won't interfere with your cat's treatments.

Frequently Asked Questions (FAQ)

Are there supplements to help a cat with kidney disease gain weight?

Many cats with renal insufficiency lose weight. Rather than utilizing a supplement, your veterinarian might try a prescription appetite stimulant like mirtazapine or capromorelin.

Why do cats with kidney disease lose weight?

Cats with kidney disease lose protein through their kidneys, resulting in muscle mass loss. Many of these kitties also have a decreased appetite, consuming fewer calories.

Our Supplements for Cats With Kidney Disease Selection Process

Catster’s dedicated team of writers and editors collaborate with expert veterinarians, considering a wide range of factors when selecting the best supplements for cats. These parameters include customer reviews, brand reputation, veterinary experience, and in some cases, hands-on testing. Of course, our cats have a say in the process, too! We strive to select and review the highest-quality products available, to help you choose the best possible product and make the most informed decision for your and your cat’s needs.

Why Trust Catster?

Catster has been a trusted online brand since 2001, so we know a thing or two about cat supplements. We’re a team of cat-loving writers, editors, and veterinarians dedicated to helping you make the most informed decision for your feline. We deeply believe in providing the best information for cat owners to help their cats live their best life possible. We look at reviews from the most trusted sources available, and this, combined with our veterinary team’s experience and expertise, helps us gather the best options on the market. Our team is invested in the welfare and health of cats around the world, and believe that expert knowledge is one of the best ways to achieve this.

Conclusion

Cats with kidney disease may benefit from a kidney supplement. Purina's Hydra Care helps your cat stay hydrated, which is essential for a kitty in kidney failure. Purina Urinary Health Crunchy Cat Treat is an affordable and balanced supplement. Dechra Porus One Kidney Powder might be a bit pricey, but studies have confirmed it to be effective in many cases.

Always consult your veterinarian before giving your cat a supplement to ensure it won't interact with its other medications.

Also see:

• How to Give a Cat a Pill: Easy Steps (Vet Answer)

• NHV Tripsy For Cats Review: Our Vet’s Opinion

Featured Shutterstock: Nils Jacobi, Shutterstock